You can't be too careful - car crashes

The class of systems with high distributed costs and focused but inadequate benefits is going to have another member: auto-calling police in the event of a car crash:

In the event of a crash, the device calls the E.U.'s 911 equivalent (112) and transmits to authorities important information including location, time, and number of passengers in the vehicle. An in-car button will also be installed in all vehicles. The eCall requirement will add an estimated $100 to the price of a car.
$100 on each (new) car sold: so how many new cars are sold in the EU each year? About 14 million in 2012. So this measure will cost $1.4 billion, and maybe $150 million in the UK. What's the benefit?
Each year nearly 26,000 people are killed in the E.U. by car crashes. This new device is estimated to reduce that number by 10 percent, saving 2,600 lives annually, by cutting down emergency response time by as much as 60 percent.
The cost of a life for purposes of safety varies by country and mode of transport, but let's take $1 million as the average. Given the quoted statistics, $2.6 billion saving (though optimistic, probably lower) comprehensively dwarfs $1.4 billion cost (though also optimistic, probably higher). Why isn't this a slam-dunk decision?

The problem is twofold: a) zeroing cost for lives saved, and b) the assumption of 10% saving. Let's consider each in turn.

If an injury is potentially fatal but not actually fatal due to timely intervention, it's almost always due to either early suppression of severe blood loss, or timely (within 1-2 mins) clearing of obstructed airway. The latter isn't relevant due to emergency service response times, so we only consider the former. This injured person will still need emergency treatment followed by several days of hospital care, and quite possibly follow-on care of injuries, rehab, and in some cases reduced lifetime tax payments due to reduced earnings and disability payments, so you're looking at order of $100K average costs. That's still not really significant.

However, consider a typical case where a life is saved: a car driver has an accident in the countryside when no-one is around. His car calls 112 and so the police (not the ambulance service initially, because they are too stretched to respond to wild goose chases) respond to his location. Seeing the crash they call for an ambulance which arrives 10-30 minutes before it would have otherwise arrived due to a passer-by report - people tend to notice a crashed car with no emergency services around it. He would have died due to shock (depletion of oxygen to the critical organs due to blood loss / asphyxiation / traumatic damage to heart and lungs) but the ambulance got there in time to oxygenate him and transport to hospital. Just how common is this?

Fatal road accidents rarely happen on remote roads - unsurprisingly, they happen where there are many more cars and roadside obstructions to run into. If an accident happens where passers-by are prevalent, this system doesn't help at all since nearly all passers-by have mobile phones. So we're only looking at a small fraction - 5% is optimistic - of accidents. The press release assumed 10%, so the benefit has already halved and is perilously close to the cost.

But bleeding to death is not a common cause of death from road accidents for drivers/passengers. Much more likely is traumatic head injury, which tends to kill them right there in the car. Unsecured drivers/passengers fly through the windscreen, or secured drivers/passengers bang their head against the car frame. This kills instantly, or in a few minutes. Another mechanism is the "third collision" where the car bangs into a tree (collision 1), the driver bangs into their seatbelt (collision 2) and then the free-hanging organs like lungs, heart bang into the drivers chest, or their blood vessels bang into ligaments that cheesewire them (collision 3). If you're in this situation and your aorta (the major blood vessel coming out of the heart) is damaged you can expect a 60%-80% chance of death no matter how quickly you get to the hospital.

Therefore, before we stick the European population with an extra $1 billion of annual costs, why don't we conduct a limited experiment introducing this requirement into a single country which is similar to another country in road crash death rates to see what effect, if measurable, this measure has? Or is the notion of trade-offs too alien to the EU?

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